# Authors: The MNE-Python contributors.
# License: BSD-3-Clause
# Copyright the MNE-Python contributors.

from pathlib import Path

import matplotlib.pyplot as plt
import numpy as np
import pytest
from numpy.testing import assert_array_equal

from mne import (
    SourceEstimate,
    pick_events,
    read_cov,
    read_dipole,
    read_events,
    read_evokeds,
    read_source_spaces,
)
from mne.chpi import compute_chpi_snr
from mne.datasets import testing
from mne.filter import create_filter
from mne.io import read_raw_fif
from mne.minimum_norm import read_inverse_operator
from mne.time_frequency import CrossSpectralDensity
from mne.utils import _record_warnings
from mne.viz import (
    plot_bem,
    plot_chpi_snr,
    plot_csd,
    plot_events,
    plot_filter,
    plot_snr_estimate,
    plot_source_spectrogram,
)
from mne.viz.misc import _handle_event_colors
from mne.viz.utils import _get_color_list

data_path = testing.data_path(download=False)
subjects_dir = data_path / "subjects"
src_fname = subjects_dir / "sample" / "bem" / "sample-oct-6-src.fif"
inv_fname = (
    data_path / "MEG" / "sample" / "sample_audvis_trunc-meg-eeg-oct-4-meg-inv.fif"
)
evoked_fname = data_path / "MEG" / "sample" / "sample_audvis-ave.fif"
dip_fname = data_path / "MEG" / "sample" / "sample_audvis_trunc_set1.dip"
chpi_fif_fname = data_path / "SSS" / "test_move_anon_raw.fif"
base_dir = Path(__file__).parents[2] / "io" / "tests" / "data"
raw_fname = base_dir / "test_raw.fif"
cov_fname = base_dir / "test-cov.fif"
event_fname = base_dir / "test-eve.fif"


def _get_raw():
    """Get raw data."""
    return read_raw_fif(raw_fname, preload=True)


def _get_events():
    """Get events."""
    return read_events(event_fname)


def test_plot_filter():
    """Test filter plotting."""
    l_freq, h_freq, sfreq = 2.0, 40.0, 1000.0
    data = np.zeros(5000)
    freq = [0, 2, 40, 50, 500]
    gain = [0, 1, 1, 0, 0]
    h = create_filter(data, sfreq, l_freq, h_freq, fir_design="firwin2")
    plot_filter(h, sfreq)
    plt.close("all")
    plot_filter(h, sfreq, freq, gain)
    plt.close("all")
    iir = create_filter(data, sfreq, l_freq, h_freq, method="iir")
    plot_filter(iir, sfreq)
    plt.close("all")
    iir = create_filter(
        data, sfreq, l_freq, h_freq, method="iir", iir_params={"output": "ba"}
    )
    plot_filter(iir, sfreq, compensate=True)
    plt.close("all")
    iir = create_filter(
        data, sfreq, l_freq, h_freq, method="iir", iir_params={"output": "sos"}
    )
    plot_filter(iir, sfreq, compensate=True)
    plt.close("all")
    plot_filter(iir, sfreq, freq, gain)
    plt.close("all")
    iir_ba = create_filter(
        data, sfreq, l_freq, h_freq, method="iir", iir_params=dict(output="ba")
    )
    plot_filter(iir_ba, sfreq, freq, gain)
    plt.close("all")
    fig = plot_filter(h, sfreq, freq, gain, fscale="linear")
    assert len(fig.axes) == 3
    plt.close("all")
    fig = plot_filter(h, sfreq, freq, gain, fscale="linear", plot=("time", "delay"))
    assert len(fig.axes) == 2
    plt.close("all")
    fig = plot_filter(
        h, sfreq, freq, gain, fscale="linear", plot=["magnitude", "delay"]
    )
    assert len(fig.axes) == 2
    plt.close("all")
    fig = plot_filter(h, sfreq, freq, gain, fscale="linear", plot="magnitude")
    assert len(fig.axes) == 1
    plt.close("all")
    fig = plot_filter(h, sfreq, freq, gain, fscale="linear", plot=("magnitude"))
    assert len(fig.axes) == 1
    plt.close("all")
    with pytest.raises(ValueError, match="Invalid value for the .plot"):
        plot_filter(h, sfreq, freq, gain, plot=("turtles"))
    _, axes = plt.subplots(1)
    fig = plot_filter(h, sfreq, freq, gain, plot=("magnitude"), axes=axes)
    assert len(fig.axes) == 1
    _, axes = plt.subplots(2)
    fig = plot_filter(h, sfreq, freq, gain, plot=("magnitude", "delay"), axes=axes)
    assert len(fig.axes) == 2
    plt.close("all")
    _, axes = plt.subplots(1)
    with pytest.raises(ValueError, match="Length of axes"):
        plot_filter(h, sfreq, freq, gain, plot=("magnitude", "delay"), axes=axes)


def test_plot_cov():
    """Test plotting of covariances."""
    raw = _get_raw()
    cov = read_cov(cov_fname)
    with pytest.warns(RuntimeWarning, match="projection"):
        fig1, fig2 = cov.plot(raw.info, proj=True, exclude=raw.ch_names[6:])

    # test complex numbers
    cov["data"] = cov.data * (1 + 1j)
    fig1, fig2 = cov.plot(raw.info)


@testing.requires_testing_data
def test_plot_bem():
    """Test plotting of BEM contours."""
    pytest.importorskip("nibabel")
    with pytest.raises(OSError, match="MRI file .* not found"):
        plot_bem(subject="bad-subject", subjects_dir=subjects_dir)
    with pytest.raises(ValueError, match="Invalid value for the 'orientation"):
        plot_bem(subject="sample", subjects_dir=subjects_dir, orientation="bad-ori")
    with pytest.raises(ValueError, match="sorted 1D array"):
        plot_bem(subject="sample", subjects_dir=subjects_dir, slices=[0, 500])
    fig = plot_bem(
        subject="sample",
        subjects_dir=subjects_dir,
        orientation="sagittal",
        slices=[25, 50],
    )
    assert len(fig.axes) == 2
    assert len(fig.axes[0].collections) == 3  # 3 BEM surfaces ...
    fig = plot_bem(
        subject="sample",
        subjects_dir=subjects_dir,
        orientation="coronal",
        brain_surfaces="white",
    )
    assert len(fig.axes[0].collections) == 5  # 3 BEM surfaces + 2 hemis
    fig = plot_bem(
        subject="sample",
        subjects_dir=subjects_dir,
        orientation="coronal",
        slices=[25, 50],
        src=src_fname,
    )
    assert len(fig.axes[0].collections) == 4  # 3 BEM surfaces + 1 src contour
    with pytest.raises(TypeError, match="when src is in head coordinates"):
        plot_bem(subject="sample", subjects_dir=subjects_dir, src=inv_fname)


def test_event_colors():
    """Test color assignment."""
    events = pick_events(_get_events(), include=[1, 2])
    unique_events = set(events[:, 2])
    # make sure defaults work
    colors = _handle_event_colors(None, unique_events, dict())
    default_colors = _get_color_list()
    assert colors[1] == default_colors[0]
    # make sure custom color overrides default
    colors = _handle_event_colors(
        color_dict=dict(foo="k", bar="#facade"),
        unique_events=unique_events,
        event_id=dict(foo=1, bar=2),
    )
    assert colors[1] == "k"
    assert colors[2] == "#facade"


def test_plot_events():
    """Test plotting events."""
    event_labels = {"aud_l": 1, "aud_r": 2, "vis_l": 3, "vis_r": 4}
    color = {1: "green", 2: "yellow", 3: "red", 4: "c"}
    raw = _get_raw()
    events = _get_events()
    fig = plot_events(events, raw.info["sfreq"], raw.first_samp)
    assert fig.axes[0].get_legend() is not None  # legend even with no event_id
    plot_events(events, raw.info["sfreq"], raw.first_samp, equal_spacing=False)
    # Test plotting events without sfreq
    plot_events(events, first_samp=raw.first_samp)
    with pytest.warns(RuntimeWarning, match="will be ignored"):
        fig = plot_events(
            events, raw.info["sfreq"], raw.first_samp, event_id=event_labels
        )
    assert fig.axes[0].get_legend() is not None
    with pytest.warns(RuntimeWarning, match="Color was not assigned"):
        plot_events(events, raw.info["sfreq"], raw.first_samp, color=color)
    with (
        _record_warnings(),
        pytest.warns(RuntimeWarning, match=r"vent \d+ missing from event_id"),
    ):
        plot_events(
            events,
            raw.info["sfreq"],
            raw.first_samp,
            event_id=event_labels,
            color=color,
        )
    multimatch = r"event \d+ missing from event_id|in the color dict but is"
    with _record_warnings(), pytest.warns(RuntimeWarning, match=multimatch):
        plot_events(
            events,
            raw.info["sfreq"],
            raw.first_samp,
            event_id={"aud_l": 1},
            color=color,
        )
    extra_id = {"missing": 111}
    with pytest.raises(ValueError, match="from event_id is not present in"):
        plot_events(events, raw.info["sfreq"], raw.first_samp, event_id=extra_id)
    with pytest.raises(RuntimeError, match="No usable event IDs"):
        plot_events(
            events,
            raw.info["sfreq"],
            raw.first_samp,
            event_id=extra_id,
            on_missing="ignore",
        )
    extra_id = {"aud_l": 1, "missing": 111}
    with (
        _record_warnings(),
        pytest.warns(RuntimeWarning, match="from event_id is not present in"),
    ):
        plot_events(
            events,
            raw.info["sfreq"],
            raw.first_samp,
            event_id=extra_id,
            on_missing="warn",
        )
    with _record_warnings(), pytest.warns(RuntimeWarning, match="event 2 missing"):
        plot_events(
            events,
            raw.info["sfreq"],
            raw.first_samp,
            event_id=extra_id,
            on_missing="ignore",
        )
    events = events[events[:, 2] == 1]
    assert len(events) > 0
    plot_events(
        events,
        raw.info["sfreq"],
        raw.first_samp,
        event_id=extra_id,
        on_missing="ignore",
    )
    with pytest.raises(ValueError, match="No events"):
        plot_events(np.empty((0, 3)))


@testing.requires_testing_data
def test_plot_source_spectrogram():
    """Test plotting of source spectrogram."""
    sample_src = read_source_spaces(
        subjects_dir / "sample" / "bem" / "sample-oct-6-src.fif"
    )

    # dense version
    vertices = [s["vertno"] for s in sample_src]
    n_times = 5
    n_verts = sum(len(v) for v in vertices)
    stc_data = np.ones((n_verts, n_times))
    stc = SourceEstimate(stc_data, vertices, 1, 1)
    plot_source_spectrogram([stc, stc], [[1, 2], [3, 4]])
    pytest.raises(ValueError, plot_source_spectrogram, [], [])
    pytest.raises(
        ValueError, plot_source_spectrogram, [stc, stc], [[1, 2], [3, 4]], tmin=0
    )
    pytest.raises(
        ValueError, plot_source_spectrogram, [stc, stc], [[1, 2], [3, 4]], tmax=7
    )


@pytest.mark.slowtest
@testing.requires_testing_data
def test_plot_snr():
    """Test plotting SNR estimate."""
    inv = read_inverse_operator(inv_fname)
    evoked = read_evokeds(evoked_fname, baseline=(None, 0))[0]
    plot_snr_estimate(evoked, inv)


@testing.requires_testing_data
def test_plot_dipole_amplitudes():
    """Test plotting dipole amplitudes."""
    dipoles = read_dipole(dip_fname)
    dipoles.plot_amplitudes(show=False)


def test_plot_csd():
    """Test plotting of CSD matrices."""
    csd = CrossSpectralDensity(
        [1, 2, 3],
        ["CH1", "CH2"],
        frequencies=[(10, 20)],
        n_fft=1,
        tmin=0,
        tmax=1,
    )
    plot_csd(csd, mode="csd")  # Plot cross-spectral density
    plot_csd(csd, mode="coh")  # Plot coherence


@pytest.mark.slowtest  # Slow on Azure
@testing.requires_testing_data
def test_plot_chpi_snr():
    """Test plotting cHPI SNRs."""
    raw = read_raw_fif(chpi_fif_fname, allow_maxshield="yes")
    result = compute_chpi_snr(raw)
    # test figure creation
    fig = plot_chpi_snr(result)
    assert len(fig.axes) == len(result) - 2
    assert len(fig.axes[0].lines) == len(result["freqs"])
    assert len(fig.legends) == 1
    texts = [entry.get_text() for entry in fig.legends[0].get_texts()]
    assert len(texts) == len(result["freqs"])
    freqs = [float(text.split()[0]) for text in texts]
    assert_array_equal(freqs, result["freqs"])
    # test user-passed axes
    _, axs = plt.subplots(2, 3)
    _ = plot_chpi_snr(result, axes=axs.ravel())
    # test error
    _, axs = plt.subplots(5)
    with pytest.raises(ValueError, match="a list of 6 axes, got length 5"):
        _ = plot_chpi_snr(result, axes=axs.ravel())
